The subject of several, free and often ambiguous interpretations, Cactus is an icon of Italian design that has revolutionized the domestic landscape by subverting the borders between indoor area and open space. Cactus comes as an ironic totem, and embodies the grit, the imagination and the humor of the design of the Seventies. Likely to draw everybody's attention, this hall-tree redeems itself from functionalism at all costs, because it can perform its function, but also be used as a merry…